Timing the engine with new timing belt?

The timing marks are on the new belt. You need to place the belt with the arrow facing towards the front of the vehicle. Then align the marks from the belt to the marks on the pulleys. On the belt there will b one line that is either a double line or a dotted line. This line will be placed on the passenger side camshaft pulleys mating mark.

Here is a link to the timing marks on the engine for the timing belt, scroll down please

https://www.2carpros.com/diagrams/nissan/frontier/1999

Please let us know if you need anything else to get the problem fixed.